A free, browser-based tool for planning any 96-well plate experiment — dose-response, growth inhibition, phage infection, dye assays, and more. Paint wells directly, calculate volumes, undo mistakes, save your work, and export to CSV or PNG. No login. No install.
Launch Dilution Designer →I use 96-well plates regularly in a plate reader — dose-response assays, growth inhibition curves, dye uptake experiments, phage infection assays. Every time I sit down to design a new experiment, I end up doing the same mental gymnastics: how much stock do I need per well? how many wells do I have for this replicate count? does this volume even pipette reliably?
I was doing it in spreadsheets, then on paper, then in my head while already in the lab — and making small mistakes that cost me an afternoon re-running controls. I wanted something I could pull up on any computer in the lab, type in my numbers, and get a plate map and bench protocol back immediately.
I also change things constantly. A colleague asks to borrow a row for their control. My stock concentration changes. I want to add a replicate. I want to design a phage infection with different MOIs across the same plate. I needed a tool that lets me adjust things on the fly and see the effects instantly — without re-doing a spreadsheet from scratch.
For concentration-gradient experiments: antibiotics, inducers (IPTG, doxycycline), small molecules, dyes, enzymes.
For MOI-based infection assays: phage dose-response, host range testing, plaque formation, infection efficiency.
Four tools: Paint (assign a condition to any well), Replicate (drag horizontally or vertically to fill a run of wells with the same condition), Erase, and Exclude. Click or drag directly on the plate map.
Ctrl+Z undoes any paint, erase, exclude, or condition change — up to 30 steps back. Ctrl+Y (or Ctrl+Shift+Z) redoes. Toolbar buttons too. One drag stroke = one undo action, no matter how many wells you swept.
Your plate, conditions, and settings are automatically saved to the browser — reload the page and everything is exactly where you left it. Use 💾 Save to download a .json file and 📂 Load to restore it on any device.
Download a crisp, retina-quality image of your plate map — condition colors, well IDs, and a footer with experiment name and date. Ready to drop into a notebook, slide, or report.
Large square wells (inspired by Biotek Gen5 software), well IDs visible in each cell (A1–H12), clear condition color fill. Each replicate is shown as its own independent well — never summed or collapsed.
Hover any filled well to see a floating tooltip with the exact formula used — numbers plugged in. For plasmid mode: (target ÷ stock) × well vol = X µL. For phage mode: (MOI × cells × vol) ÷ titer = X µL. No more guessing how a volume was calculated.
Enter an impossible value — zero stock concentration, an intermediate that exceeds your stock, a negative titer — and you get a red border with an inline error immediately. Volume warnings appear when your planned pipetting would exceed the stock or culture you have available.
Standalone calculator in the sidebar: enter bacterial concentration (CFU/mL), phage titer (PFU/mL), desired MOI, and infection volume — get the exact phage volume to add in µL.
Plan a dilution series from stock to working titer. Set your minimum pipettable volume — the planner enforces it at every step and outputs a complete recipe with transfer and diluent volumes.
Day (bright, high-contrast), Night (dark mode), and Ambient (warm, low-contrast — easy on the eyes during long bench sessions). Toggle in the header. Your choice is remembered.
Click any condition swatch or control dot to open a color picker. Choose from a quick palette or enter a custom hex code — the plate map updates live.
Click row/column buttons to exclude entire rows or columns. Or use the Exclude tool and drag directly on the plate to mark individual wells as off-limits. Excluded wells show a striped pattern and are omitted from all calculations.
Toggle negative controls, media blanks, culture blanks, and positive controls — each with their own color. Add custom controls for any use case.
Automatically calculates master mix volumes with 10% overage so you don't run out mid-experiment. Groups by condition and lists all well IDs in each group.
Download a JSON (full experiment state), CSV (full or minimal), or PNG plate image. Copy a plain-text protocol summary, print the full bench report, or print just the plate map.
If your stock is too concentrated to pipette directly, switch to intermediate stock mode and get a recipe for making the right dilution first.
Name your compound or reagent — it appears throughout the protocol, legend, bench instructions, CSV header, and PNG footer so your exports are self-documenting.
Dilution Designer works for any assay that uses a 96-well plate. Some examples of where it's useful:
.json file you can reload on any computer. Hover any filled well to see the calculation breakdown with your actual numbers.
Free, browser-based, no account required. Open it on any computer in the lab.
Launch Dilution Designer →Found something broken? Have an idea for a new feature? Want support for a different assay type or plate format? I want to hear about it.
Something isn't calculating correctly, a button doesn't work, or the layout breaks? File a bug report on GitHub.
Report a bug →Want support for a new plate format, a different export option, or a specific assay workflow? Open a feature request.
Request a feature →Questions, suggestions, or just want to say the tool saved you time? Open an issue on GitHub — all feedback is welcome.
Open GitHub Issues →Source code is at github.com/mbaffour/dilution-designer